The most common locations for a thyroglossal cyst is midline or slightly off midline, between the isthmus of the thyroid and the hyoid bone or just above the hyoid bone. A thyroglossal cyst can develop anywhere along a thyroglossal duct, though cysts within the tongue or in the floor of the mouth are rare.
A thyroglossal cyst will move upwards with protrusion of the tongue.
Very rarely, the persistent duct can become cancerous, called thyroglossal duct carcinoma. In the case of thyroglossal duct carcinoma, the cancerous cells are ectopic thyroid tissue that has been deposited along the thyroglossal duct and usually follows exposure to radiation.
The persistent duct or sinus can promote oral secretions, which may cause cysts to become infected. Up to half of thyroglossal cysts are not diagnosed until adult life. The tract can lie dormant for years or even decades until some kind of stimulus leads to cystic dilation. Infection can sometimes cause the transient appearance of a mass or enlargement of the cyst, at times with periodic recurrences. Spontaneous drainage may also occur.
Surgical management requires excision not only of the cyst but also of the path's tract and branches. A removal of the central portion of the hyoid bone is indicated to ensure complete removal of the tract. It is unlikely that there will be a recurrence after such an operation. At times antibiotics can be indicated if there is sign of infection.
Thyroid scans and thyroid function studies are ordered preoperatively, this is important to demonstrate that normally functioning thyroid tissue is in its usual location.
Papillary carcinoma arising in a thyroglossal duct cyst with associated microcarcinoma of the thyroid and without cervical lymph node metastasis: a case report.(Case report)
Feb 08, 2008; Authors: Tolga Kandogan (corresponding author) ; Nazif Erkan ; Enver Vardar IntroductionAs the thyroid gland descends...